Stepping contact arrangement



May 25, 1954 F, RAUPACH x 2,679,558

` STEPPING CONTACT ARRANGEMENT Filed Dec. ll, 1951 4 Sheets-Sheet l -i.- u) v FRIEDRICH RAUPCH May 25, 1954 F, RAUPACH 2,679,558

STEPPING CONTACT ARRANGEMENT Filed DSC. ll, 1951 4 Sheets-Sheet 2 FRIEUKIH RAUPAQH May 25, 1954 F. RAuPAcH 2,679,558. STEPPING CONTACT ARRANGEMENT Filed Dem. 11, 1951 4 Sheets-Sheet 4 FIG.5

INVENTOR FRlenR/CH RAUPACH Patented May 25, 1954 2,679,558 STEPPIN G CONTACT ARRAN GEMEN T Friedrich Raupach, Bamberg, Application December 11, 1951, Serial No.

8 Claims. 1

The present invention relates toa process and appropriate device for carrying out the stepped regulation,

For regulating transformers, it is known for example to have the bare turns of the regulating winding tapped by meansof a switching member. For this purpose, the regulating winding surrounding the iron core is, for example, rotatably wound, whilst an axially displaceable current collector slides along the turns. It is also known, to dispose the regulating winding xedly and to guide the current collector, which slides on the turns, around the winding, tracing a helical path.

Both processes and their devices for carrying them out, are, however, not satisfactory. Rotatable regulating windings require special and very accurate mountings, which have to be dimensioned individually for each transformer capable of regulation; also, the winding has to be bare for the whole length. Still more disadvantageous is the process of guiding the current collector, which slides on the regulating winding, on a helical path about said winding; such current collectors have a complicated construction and necessitate considerable expenditure of materials and auxiliary devices, such as mountings and the like.

The advantages of stageless regulation, which the known processes possess, are outweighed by the inconveniences mentioned. Efforts were therefore made in other directions, and experiments were made using a metal roller as the current collector, this metal roller was made to run on a regulating winding consisting of two conductors which were wound in the same direction side by side and were preferably connected with each other by way of a choke coil or a resistance. This proposal brought somewhat nearer the solution of the problem of uninterruptedly supplying or deriving fairly heavy currents whilst avoiding complicated rotatable tapping methods. However, the higher expenditure of material winding space caused by the doubling of the winding proves so disadvantageous that this process is also not satisfactory.

It was therefore proposed to employ a carbon roller as current collector instead of the metal roller. The capacity of such regulating transformers is very limited however, because the potential differences of the windings amount to hardly more than one volt and the carbon roller may only carry a maximum load of about 40 amperes. In view of the useful length of the iron core and thus of the length of the winding and the number of turns, this loading normally corresponds to a three-phase output of roughly For the regulation of larger outputs, the booster and rotary transformers, are, indeed,

Germany available; they regulate Without stages. However,` their use is only economically justified with considerably'higher outputs, because such transformers are very expensive on account of the large amount of material required and their mechanical construction.

The problem still remained of producing a cheap and simple process and corresponding device for carrying .out the regulation, in as ne electrical outputs, especially for regulating transfarmers, resistance, etc. The upper limit here is constituted roughly by the smallest output at which booster and step transformers are still economic.

According to the invention a process for the stepped regulation, particularly ne regulation, of fairly large electrical outputs by tapping, particularly in connection with regulating transformers, regulating resistances and the like, in which individually spaced contact points are switched in and out again .by means of switching members, is characterised by the feature that for the execution of switching steps at least two contact or switching members disposed and actuated. in a supporting means guided along a row of contacts, are used alternately, but without interruption of the supply or discharge of current, in such a manner that, while one contact member is touching one contact point, the other contact member, advancing and omitting being touched by the rst contact member, moves onward and is placed upon point, whereupon, directly thereafter, the first contact member is lifted very rapidly, preferably in a jerky manner, from its contact point and, skipping the contact point being touched by the second member, is placed upon the next contact point.

The process according to the invention has in particular the advantage that it affords a very reliable, readily adjustable and easily inspected supply and discharge of current; each individual switching stagev is switched in and out positively because the switching members alternating with each other are placed upon the contact points with predetermined pressure and on precisely prescribed paths and are lifted 01T from the contact points again with equally positive precision. This reliable contact making and breaking ensures a completely satisfactory supply and discharge of current for each separate contact point of the entire contact path, whereas it often happens for instance with stageless regulation havvices that the contact pressure varies considerably in the course of the regulating, so that more or less high transition losses may occur.

In contrast to this, the process according to the invention offers the great advantage that very high specific contact pressures are employed. It permits in particular, when the switching members consist of very efficient conducting materials, the withdrawal or supply of currents of 200 amps. or more. The potentials between the individual turns of the regulating winding can also amount to many times the potentials of the turns permissible when carbon rollers are used as the current collector. These advantages of the process according to the invention are in turn based on the fact that each switching member, after it has relieved the other, is raised, with, as it were, a jerking movement from the contact point hitherto touched by it. In given cases, preferably with metal switching members, it is to be recommended to connect the latter with each other by way of a resistance capable of being heavily loaded, in order to render ineffective the circulating currents occurring on the simultaneous touching of two switching members.

The process and the device according to the invention have further the advantage that the winding space is more favourably utilised, so that, for instance, the regulating winding may consist of a single, bare, conductor placed on edge. It is, however, also possible to use instead of a bare conductor an insulated conductor from which the covering has been removed in suitable places.

It is further found that the advantages obtainable on using the process according to the invention are increased if springs are used in known manner in order to introduce or carry out certain operations in an accelerated manner, e. g. the movement of the switching member, or to hold positively for a certain space of time some of the working parts, so that on release a more definite action results. It is particularly recommended to employ a power accumulator in such a manner that, while one switching piece rests upon its contact point, the power accumulator, e. g. a clockwork-type spiral spring, is charged against a locking mechanism, whereupon, after unlocking by release of the spring force, the switching operation is suddenly introduced and carried out in such a manner that the lifted switching member is moved on by the amount of the switching step and lowered onto the next contact point, and directly after the seating of this switching piece has taken place, the other switching piece is lifted and carried after it.

According to the invention, the switching step movements and the raising and lowering movements of the switching members each have their own driving mechanism, which operates separately and is actuated or controlled by a central driving shaft.

For pressing the switching pieces onto the contact points it is also an advantage to accommodate in the holding means a power accumulator which is charged positively, preferably by the switching piece itself, while the latter is travelling over the path from one contact point to the other.

For releasing the power accumulator actuating the central driving shaft switching step by switching step, it is possible to use for instance chain or worm drives guided into the holding means from the outside. When worm drives are used, it is readily possible to use the driving means as used for the feed in sliding and screw cutting lathes. When less sensitive chain drives are used, chains after the style of bicycle chains are recommended. It is, however, also possible to equip the holding means with an electric motor or with electro-magnets which act either directly or indirectly on the driving means for the advance of the holding means and for actuating the switching pieces. f the holding means is guided on rails, friction wheels or the like, which are driven by the electric motor or by electric magnets which actuate for instance cams, these cams act on the guide rails in order thereby to cause the advance. In addition to or instead of rnechanical or electrical driving or control means it is, however, also possible to employ hydraulic driving means.

'For carrying out the-process of stepped forward switching according to the invention, various devices are possible.

A contact arrangement according to the present invention which is to be used with at least two sets of alternately arranged contact faces which are spaced from each other in at least one direction, comprises, in combination, supporting means; at least two contact members movably mounted on the supporting means, each contact member being associated with one of the two sets of contact faces, the contact members being movable in the one direction, each contact member being also movable in a transverse direction between a retracted position, and an advanced contact position for engaging a contact face of the associated set of contact faces; advancing and retracting means movably mounted on the supporting means and connected to the contact members for independently advancing and holding each contact member in the advanced contact position in contact with a contact face of the associated set of contact faces and for independently retracting each of the Contact members; shifting means mounted on the supporting means connected to the contact members and alternately moving each of the contact members in the retracted position in the one direction from one contact face to the next contact face of the associated set of contact faces, and simultaneously holding the other of the contact members temporarily immovable n the advanced contact Dosition engaging a contact face located between the one contact face and the next contact face and means movably mounted on the supporting means and connecting the advancing and retracting means and the shifting means for operation in a predetermined sequence.

The advancing and retracting as well as the shifting of the contact members from one contact face to the next engaged contact face may be carried out by hydraulic means.

A preferred form of construction according to the invention for carrying out the process is 0btained by using an eccentric control for the movement of the switching members, which eccentric control is preferably provided with a straight guide. The eccentric control may be driven by the central driving shaft which controls the advance of the holding means for the switching members and which is positively externally controlled by way of a chain drive, worm drive or the like. On the two front faces of the disc-shaped driving shaft, eccentric pins, which may be adjustably disposed, are provided for the step-wise moving of the switching members along the contact path. On the eccentric pins increasing the eccentric action, further cams, eccentrics or the like are provided, in order to raise the switching pieces as quickly as possible from the contact path. These two eccentrics connected with each other make possible in a particularly simple and maracas leiective manner fboth the advance movement Iand 'the vplacing Yon and lifting 01T of the switching larly veflicient controllable advancement and lifting and lowering :movements of the switching members.

l'switching member is so ldisposed that, without lowering or raising it, but sliding along in the :switching piece, e. g. in a longitudinal slit thereof, V.it pushes the switching member forward in free end which passes Vthrough and points outwards carries the second eccentric. This eccentric preferably acts on a bolt, which is detachably path and in a plane vertical to this path, which guiding means may also be utilised for the supply :anddischarge of curren It has vfurther proved advantageous to dispose the rails symmetrically c The `invention will be further described by way of example with reference to the accompanying diagrannnatical drawings in which:

Fig. 1 shows in perspective view three different operating positions of the device provided with eccentric control according to the invention.

Fig. 2 shows a section vertical to the guiderails across the holding means of the switching pieces and their actuating means.

Fig. 3 shows a longitudinal section along the plane A-B in Fig. 2.

Fig. 4 Vshows :a :further longitudina. .section `'along the plane C- Diin Fig.2.

Fig. 5 is 'ai/perspective viewfof an arrangement .according `to the present invention.

The saine parts in the various figures and indi vidual representations are denoted by identical reference numbers.

The example of construction, shown in the during various operating positions I, II and III. The sequence of the three operating positions illustrated is in the direction of the arrow 4 in the drawings, i. e. from left to right.

The contact surface i, which is shown in Figs. 2 and 3 for'the sake of clarity, only by a line, is represented in Fig. 1 by two sections 2 and 3,

,iecting bolt 9 1s secured to theswitching meL ber 5. A cylindrical helical pressure spring (not shown) acts on the top face I0 ofthe switching member 5 in the line of Vaction indicated by arrow il.

On the `other switching member 5, the sharp designated I3, vllt or I5 respectively. The line of action of the pressure spring `or `the like (not shown) is numbered it.

A disc-shaped driving shaft l1 is-disposed bernanner or a bicycle. The axis of rotation I8 of :the drivingshaft IJ is parallel to the contact path l, k2, 3. The facevi driving shaft l1 facing white, thus clarifying the positionof I1 during the various operating positions. Arrow 2c indilCates the direction of rotation 'of the driving '.shaft H.

On the forwardly :facing frantoi the driving yshaft I l yan eccentric vor crank pin'2l is provided :which pin passes'through the slot 3 on the switchzingmeinber v5 and on .its-free end carries a circu lar disc 22, whlch is likewise leccentrically disposed in such a manner, :that with thecrank pin 2li afdouble eocentric2i, Z2 is formed.

Freni the face offthe-driving'fshaft i'iremote from the observer, ra crank Apin 23 projects through the slot :i3 gin-the switching member 6,

Aandcarries on its free end eccentricaily'disposed disc 24.

Thediscs'ZE and'd zzo-operate withbolts-S and `lil respectively iixedly disposed on the switching'rneinbers E-and 6.

'The disc `22, ,acting -as va double eccentric, is

lifted and `turned when rotationvof the driving shaft i ltakes place inthe direction of thearrow 26. kWhen the position of the driving shaft I1 surface.

On further rotation of the driving shaft il, the disc 22 lifts the bolt 3, which is now bearing on it, together with the contact 1, very quickly or positively off the contact point 2, against the action of the spring acting on surface |0. The slots 8 and |3 have the purpose of keeping the switching members and 6 in contact with the path l, 2, 3 independently of the advancing movement of the step and switching mechanism, as shown in detail by the illustration I, II, in Fig. l.

The described form of construction of the device according to the invention operates substantially as follows:

In position I of Fig. l, under the action of a spring the switching member 5 is held firmly in contact with the section 2 of the regulating winding, which section is constructed as a contact The actuating disc 22 is remote from the bolt 9. On the other side of the driving shaft l1, the eccentric disc 24, however, holds the switching member 6 away from the contact surface 3 of the regulating winding by pressure on the bolt |4 against the direction of action oi the spring or the like (not Shown).

In the further course of operation of the device, the driving shaft |1 is rotated through about 90 in the direction of the arrow 26. The operating position is now as shown in position II of Fig. l. The crank pin 2| has travelled upwards in the slot 8 of the switching member 5, without, however having raised the said member from the contact point while so doing; this is prevented by the pressure spring. The crank pin 23, because of its eccentricity in relation to the crank pin 2 i,

has moved the switching member 6 above the contact point. The ow of current continues through member 5 as the pressure of the spring on this member keeps it in contact with surface 2. In the meantime, the switching member has moved downwards in the direction of the arrow I6, onto the contact point 3 under the action of its own spring, because the eccentric disc 24 has separated from the bolt |4 by rotation through 90 of the disc 24. The bolt |4 thus released moved downwards together with the member 6, the eccentric pin 23 sliding in the slot i3 in the member and in this way allowing the downward movement.

In the working position III, the driving shaft l1 is again shown rotated through a further 90 i in the direction of the arrow 20. On its rotation into the operating position shown, the doubly eccentrically mounted control disc 22 has raised the bolt 6 with the switching member 5 very quickly with a jerk as it were, against the spring force from the contact surface 2 which it had hitherto touched. At the same time, the crank pin 2| has moved the switching member 5 further by one switching step in the direction of the contact path, which step results from the rotation of the crank pin through 90 out of the operating position II into the operating position III. In the meantime, the eccentric disc 24 has been as far separated from the bolt |4 of the switching piece 6 as the eccentric disc 22 and the bolt 9 are separated in the operating position I.

The cycle of work of the switching and driving mechanisms continues as described; after two further switching steps each with 90 rotation of the driving shaft, the starting point shown in diagram I would be reached again, only the contact points are then correspondingly different.

Figs. 2-4 illlustrate the development of the example of construction shown of the device according to the invention.

In Fig. 2, 25 and 26 are the two halves of the casing of a switching mechanism between which there is a joint 21. The mechanism is supported on rails 34 and 4|. The joint 21 is provided because rails, on which the casing is guided and suspended, pass through the casing longitudinally. The joint makes possible a solid t of the casing parts on the rail surfaces and obviates any play. The two casing parts 25, 2B support each other not directly, but by way of the rail, they can be held together in known manner, e. g. by means of bolts.

In the top section of the half casing 25 a recess 28 is provided, said recess extending along the upper of the two aforementioned rails. Opposite the lengthwise surface of the rail there is in the base of the recess 25 a strip 29 consisting for instance of copper. Between this strip and the rail a corrugated spring band 36 is disposed, which serves for transmitting current when the supporting and guiding rail is at the same time used as an electrical conductor. In this case, the current is led into and away from the switching piece by way of a cable 19.

The corresponding recess, strip and spring provided in the casing half 26 are numbered 3|, 32 33 respectively. The parts described above are also duplicated in the lower section of the casing halves 25 and 26. In the half 25, the recess, the conductor and the spring strip are numbered 35, 36 and 31 respectively; correspondingly in the casing part 26 they are numbered and 40. The lower supporting and guiding rail is numbered 4| (see also Figs. 3 and 4).

Inside the casing 25, 26 and about the central 'transverse axis two fairly large symmetrical recesses l2 and 43 are provided. These recesses receive the driving mechanism. In the example of construction shown, a driving shaft il with chain wheel 40 and lengthwise passing chain 56 is shown. The driving shaft l1 is supported within the casing parts 25 or 25 by way of axial ball bearings 44 and 45. Between the rings of the ball bearings, a ring 45 slides in the driving shaft l1; this ring is of U-shaped cross-section and is disposed with the opening at the side. Between the shanks of this ring there is a power storing means consisting substantially of a spiral spring 41. The U-shaped ring 46 is embraced externally by the hub 48 of the chain wheel, which is firmly fitted on the ring. A chain 50 engaging in the teeth can be seen in the section of Fig. 2, and in Fig. 5 but is omitted in Figs. 3 and 4.

Between the U- haped ring body 46, which is mounted so as to be loosely rotatable on the driving shaft l1, and the two ball bearings 44 and 45, are situated angular rings 5| or 52. The ring 5l has two recesses |01 which are staggered by 180 to each other, and in one of which, in the operating position shown, the bolt 53 engages, which has at its end remote from engagement a tapered projection 54, which is surrounded by a cylindrical helical spring 55 whichi acts as an expanding pressure spring and rests between the shoulder of the bolt 53 and the base of a recess 51 in the casing half 25, or abuts against these two parts. The projection of smaller diameter 5s engages in a guide bore 56 in the casing half '25.

The spiral spring 41 accommodated in the U- shaped ring 46 is secured, at the top side of the ring 45, to the ring 5| by its end adjacent to the driving shaft l1, while the other end is firmly fixed to that side of the U-shaped casand thus the switching member is raised. rapidly, with. a. jerk, as it. were, fromY the: contact. path.

The circular space 63/ in the.. bearing body 58 continuesv upwardly into a roughly cylindrical recess 64 in; which the. cylindrical. helical spring 65 is` partly accommodatedA andabuts against the base-oftherecess. Opposite. the. recess ed there ingring 46 which faces-'the' chainwheel. 49: Two cams |302 offset by 180 for actuating. the springloaded bolt 53. are disposed on this ring 46.

On.'v the rotation of the chain wheel 49, for effecting the switching. process, the spiral spring 41- is tensioned, as the ringv 5| remains stationary- After rotation: of the chain wheel and of the casing es rmly coupled with it through is. situated in the bearing` body 58.,4 a recessr 66, about 180, one of the two cams |92 raises the which serves as the mounting of the bolt-shaped bolt. 53,. which locks the ring 5|', against. theacl0 switching. member 5. which DELSSBSV hlflllghl ttionfof the spring 55.. By thisY meansthe ring 51| They tightly enclosing recess 66 is followed in a xedly disposed' on the spindle |1. is remased, direction towards the contact path. by the slotso that the accumulatedaforce of the spiral spring shaped recess in the limb. 59 of the casing part 4'.' turns the shaft l'! further with a sudden movement, until'the second recess inthe ring` 5|, which l5 of thev switching` member 5, which is caused by is-xofset by 180, is locked by the bolt 53,. wheretothe saidy limbs with' the aid of. bolts (not illustra-ted) whose centre line has the reference numsimultaneously for a Very short time.l ber i. The covering plate., is provided On bothsides of the driving shaft l are disroughly opposite the Spring. with a recess 70, posed: the eccentrics for moving the switching 25 through which the current supply cable 7| con- Y v nected to the cable bolt 9 passes, which cable longitudinal bodies 53 and. 12, which in turn are is guided to a resilient contact ledge 37. mounted 0n the casing.v 25,. 25.y so asy t0 be dis The bearing body 72 described in the 'OllOW- placeable in the longitudinal direction of the rails and the appropriate rafts al', fGl. i118 Sake 0f 34, 4|, For thisk purpose, the middle parts of so symmetry and uniformity relative tothe. bearthe casing form lateral. limbs which at the top ing body Iirst described, provided with reference and at the bottom engage over or under the bearnumbers only in isolated eases. The recess in ing pedestalsfor the switching member and the the bearing body 'I2 receiving the cylindrical eccentric, between which limbs the plate-shaped helical spring 13v is numbered 14. The eccentric guide bodies are slidingly movable.k This mobility 3./ disc 24 moves in the circular recess 'l5 in the of they bearing pedestals makes possible the. stepn bearing body and sflfmly tted to the crank pin wise switching onwards` of the two switching 23 which is-seatedinthe driving shaft in stagmembers, caused by the eccentrics. The contact gered relationship t0 the Crank pin 2| (Cf- Fgpressure requiredv and the raising of the switch- 2). ing members is accomplishedY by means of further lo casing part 26v engaging above and below it are eccentrics, as already illustrated with reference to the diagrammatically represented Fig. 1.

In Fig. 2, the left-hand sliding bearing body is numbered 58. It is sl-idingly supportedY on the limb 5S of the casi-ng part 25.

good t, the body 58 so set back on the sliding bearing surface that it is only supported by the comparatively narrow ledge Eil.

limb of the middle part of the casing 25 is num'- 58 over w ich 6l passes is provided along the sliding track on the lower side of the limb- 53 with a groove 62, through which, corresponding bered 6|. The top surface of the bearing body to the ledge Si), twoy sliding ledges not dened ing body l58 along the limb 6|.

The bearing body 58 has recesses for the various eccentrics or their furthest extending working orbits and for the switching piece 5 and the spring. The circular recess 63 (Fig. 3) gives space for the eccentric 22 controlling the lift movements of the member 5. This eccentric is rmly tted to afurther eccentric pin or crank eccentric disc 2.2, by means of which thev bolt 75 For ensuring sliding with as little friction as possible and a |14, which is` preferably detachably secured, e. g. screwed in, to the top.f end of the switching mem- The crank pin 23 passesv through the slct |3v inthe` contact member. The cable 1.9 is secured ina manner (not shown) at the` point 3|] of screws, one of which is indicated by its centre line. 18. y

The method of operation of the devicev for actuating the switching members according to Figs. 2 4 corresponds to the method of operatated with. a jerking motion is described.v above, sets the crank pins 2|, 23 and the double-eccentrically tted discs 22, 24 into revolution,

centric 24,. through the action of the spring 13.

I claim:

1. In a device of the character described in combination, two sets of first contact members, each first contact member having a contact portion, said first contact members being arranged so that the contact portions within each set of first contact members are arranged spaced from each other and the contact portions of one set of first contact members are arranged along a path being parallel to the path along which the contact portions of the other set of first contact members are arranged; a contact arrangement including supporting means; means for moving said supporting means in the direction of and along said paths; two second contact members mounted on said supporting means movable toward and away from said contact portions of said sets of iirst contact members, respectively; means movably mounted on said supporting means for moving one of said second contact members within spaced time intervals between the contact faces of consecutive first contact members of one of said sets of first contact members by retracting said one second contact member from one contact face, moving it toward the next contact face and advancing it onto the same; and means movably mounted on said supporting means for moving the other of said second contact members in the time intervals between said spaced time intervals when said one second contact member moves between the contact faces o' consecutive first contact members of the other of said sets of first contact members by retracting said other second contact members from one contact face, moving it toward the next contact face and advancing onto the same.

2. For use with an apparatus having at least two sets of alternately arranged contact faces which are spaced from each other in at least one direction, a contact arrangement, comprising, in combination, supporting means; at least two contact members movably mounted on said supporting means, each contact member being associated with one of said two sets of contact faces, said contact members being movable in said one direction, each contact member being also movable in a transverse direction between a retracted position, and an advanced contact position for engaging a contact face of the associated set of contact faces; tracting means movably mounted on said supporting means and connected to said contact members for independently advancing and holding each contact member in said advanced contact position in contact with a contact face of the associated set of contact faces and for independently retracting each of said contact members; shifting means mounted on said supporting means connected to said contact members and alternately moving each of said contact members in said retracted position in said one direction from one contact face to the next contact face of the associated set of contact faces, and simultaneously holding the other of said contact members temporarily immovable'in said advanced contact position engaging a contact face located between said one contact face and said next Contact face and means movably mounted on said supporting means and connecting said advancing and retracting means and said shifting means for operation in a predetermined sequence,

3. For use with an apparatus having at least two sets of alternately arranged contact faces which are spaced from each other in at least one advancing and rec direction, a contact arrangement, comprising, in combination, supporting means movable at least in one direction; means for moving said supporting means in said one direction; at least two contact members movably mounted on said supporting means, each contact member being associated with one of said two sets of contact faces, said contact members being movable in said supporting means in said one direction and in a direction opposite thereto, each Contact member being also movable in a transverse direction between a retracted position, and an advanced contact position for engaging a contact face of the associated set of contact faces; means for independently advancing and holding each contact member in said advanced contact position in contact with a contact face of the associated set of contact faces; means for independently retracting each of said contact members; a rotary member rotatably mounted in said supporting means; means for rotating said rotary member; and eccentric means secured to said rotary member spaced from the axis of rotation of the same and being connected to said two contact members for alternately moving each of said contact members in said retracted position in said one direction from one contact face to the next contact face of the associated set of contact faces during movement of said movable supporting means in said one direction, and for simultaneously moving the other of said contact members in said supporting means in said opposite direction so that said other of said contact members remains temporarily immovable in said advanced contact position engaging a contact face located between said one contact face and said next contact face. 4. For use with an apparatus having at least two sets of alternately arranged contact faces which are spaced from each other in at least one direction; a contact arrangement, comprising, in combination, supporting means movable at least in one direction; means for moving said supporting means in said one direction; at least two contact members movably mounted on said supporting means, each contact member being associated with one of said two sets of contact faces, said contact members being movable in said supporting means in said one direction and in a direction opposite thereto, veach Contact member being also movable in a transverse direction between a retracted position, and an advanced contact position for engaging a contact face of the associated set of contact faces, each contact member being formed with an elongated slot extending in said transverse direction; resilient means for independently advancing and holding each contact member in said advanced contact position in contact with a contact face or the associated set of Contact faces; means for independently retracting each of said contact members; a rotary member rotatably mounted in said supporting means intermediate said contact members and having an axis extending normal to said one direction and to said transversf direction; means for rotating said rotary member; and two diametrically arranged actuating pins secured to said rotary member spaced fron the axis thereof and projecting parallel to sai( axis in opposite directions into said elongater slots of said contact members; said actuatin pins constituting means for alternately movin each of said contact members in said retracte position in said cnc direction from one contar. face to the next contact face of the associate set of contact faces during movement of sai 13 movable supporting means in said one direction, and for simultaneously moving the other of said contact members in said supporting means in said opposite direction so that said other of said .contact members remains temporarily immovable and said next contact face.

5. For use with an apparatus having at least two sets of alternately arranged contact faces which are spaced from each other in at least one direction, a. contact arrangement, comprising, in combination, supporting means movable at least in one direction; means for moving said supporting means in said one direction; at least two contact members movably mounted on said supporting means, each contact member being associated with oneof said two sets of contact faces, said contact members being movable in said supporting means in said one direction and in a direction opposite thereto, each Contact member being also movable in a transverse direction between a retracted position, and an advanced Contact position for engaging a contact face of the associated set of contact faces, each contact member being formed with an elongated slot extending in said transverse direction; resilient means for independently advancing and holding' each contact member in said advanced contactI position in contact with a contact face of the associated set of contact faces; a rotary memtating saidrotary member; two diametrically arranged actuating pins secured to said rotary member spaced from the axis thereof and projecting parallel to said axis in opposite direcelongated slots of said contact members; said actuating pins constituting means for alternately moving each of said contact members in said retracted position in said one direction from one contact face to the next contact face of the associated set of contact faces during movement of said movable supporting means in said one direction, and for simultaneously moving the other of said contact members in said supporting means in said opposite direction so that said other of said contact members remains temporarily immovable in said advanced contact position engaging a contact face located between said one contact face and said next contact face; at least two cam members secured to said actuating pins; and at least two projecting members each secured to one of said contact members and being alternately engaged by one of said cam members during rotation of said rotary member, said cam members and said projecting' members constituting means for independently retracting each of said contact members.

6. For use with an apparatus having at least two sets of alternately arranged contact faces which are spaced from each other in at least one direction, a contact arrangement, comprising, in combination, supporting means movable at least in one direction; means for moving said supporting means in said one direction; at least two support members mounted in said supporting means movable in said one direction and in an opposite direction independently of each other; two contact membe each contact member directions into said mounted in o-ne of said support members for movement therewith in said one direction and in said opposite direction, each contact member being associated with one of said two sets of contact faces, each contact member being also movable in a transverse ldirection in the associated support member between a retracted position, and an advanced contact position for engaging a contact face of the associated set of contact faces, each contact member being formed with an elongated slot extending in said transverse direction; resilient means mounted in each of said support members for independently advancing and holding each contact member in said advanced Contact position in contact with a contact face of the associated set of contact faces; a rotary member rotatably mounted in said supporting means intermediate said` contact members and having an axis extending normal to said one direction and to said transverse direction; means for rotating said rotary member; two diametrically arranged actuating pins secured to said rotary member spaced from the axis thereof and projecting parallel to said axis in opposite elongated slots of said contact members; said actuating ping constituting means for alternately moving each of said contact members in said retracted position in said one direction from one contact face to the next contact face of the associated set of contact faces during movement of said movable supporting means in said one direction, and for simultaneously moving the other of said contact members in said supporting means in said opposite direction so that said other of said contact members remains temporarily immovable in said advanced contact position engaging a contact face located between said one contact face and said next contact face; at least two cam members secured to said actuating pins; and at least two projecting members each secured to one of said contact members and being alternately engaged' by one of said cam members during rotation of said rotary member, said cam members and said projecting members constituting means for independently retracting each of said contact members.

7, An arrangement as claimed in claim 4 wherein said means for rotating said rotary member include nrst means movably mounted on said rotary member; second means xedly secured to said rotary member and located adjacent said rst means; spring means connecting said iirst and second means; arresting means for arresting said second means and thereby said rotary member; means for rotating said iirst means whereby said spring is tensioned; and releasing means for releasing said arresting means and connected to said rotary member for rotation and for releasing said arresting means in predetermined relative positions of said rst means and said rotary member so that the recoil action of the released tensioned spring means effects a rapid. actuation of said contact members.

8. An arrangement as claimed in claim 7, and including supporting rails passing through said movable supporting means and supporting the same for movement in said one direction.

No references cited. 

